The invention relates to a method, with which perception of the contents of an image becomes possible for the blind and for persons, whose vision is highly impaired. The invention also relates to an apparatus for carrying out the method.
According to the known state of the art, which is documented by the German Offenlegungsschrift 23 30 403, there are visual aids for the blind, which project electrical potential images with the help of an electrode matrix directly from the image source onto the skin of the forehead or a finger. Since the electrical resistance of the skin must be overcome, appreciable electrical voltages, which are harmful in the long run, are required at these electrodes and undesirable galvanic and thermal side effects occur and the spatial resolution is very slight, so that one cannot actually speak of true image recognition.
It is an object of the invention to make available for a blind or visually impaired person an aid for image recognition and orientation within his surroundings, in that his limited optical perception capabilities are compensated for by technical aids in cooperation with other operative sensing organs of the impaired.
Pursuant to the invention, this objective is accomplished by a method, which comprises the following steps. First, optically detecting an image content by an image detection device used by a visually impaired person. Second, computer-aided processing image information from the image detection device. Third, transferring processed image information to a monitor matrix, worn in a scanning region of the tongue of the impaired person for representing associated image structures. Finally, scanning image structures produced by the monitor matrix by means of the tongue of the impaired person and, with that, effecting sensory detection of the image content and/or control of computer parameters by action upon sensors in the monitor matrix, by means of the tongue of the impaired person.
In an embodiment of the invention, signals for representing image information, which are processed electronically, are transferred to a flat monitor matrix, which can be worn in the oral cavity in the tactile region of the tongue. Potential distribution images, temperature distribution images or relief images are used as representation principles by the flat monitor matrix.
A feature of the present invention includes for generating an electrical current density image, the actuators of the matrix consisting of electrode pairs contacted by line and column leads, and each image point being assigned to a local current flow within an individual electrode pair.
According to a further distinguishing feature of the invention, the monitor matrix has sensors, which detect the position of the tip of the tongue on the monitor matrix for controlling computer parameters.